diff options
Diffstat (limited to 'block.c')
| -rw-r--r-- | block.c | 95 |
1 files changed, 60 insertions, 35 deletions
@@ -807,6 +807,57 @@ const BdrvChildRole child_format = { .drained_end = bdrv_child_cb_drained_end, }; +static void bdrv_backing_attach(BdrvChild *c) +{ + BlockDriverState *parent = c->opaque; + BlockDriverState *backing_hd = c->bs; + + assert(!parent->backing_blocker); + error_setg(&parent->backing_blocker, + "node is used as backing hd of '%s'", + bdrv_get_device_or_node_name(parent)); + + parent->open_flags &= ~BDRV_O_NO_BACKING; + pstrcpy(parent->backing_file, sizeof(parent->backing_file), + backing_hd->filename); + pstrcpy(parent->backing_format, sizeof(parent->backing_format), + backing_hd->drv ? backing_hd->drv->format_name : ""); + + bdrv_op_block_all(backing_hd, parent->backing_blocker); + /* Otherwise we won't be able to commit or stream */ + bdrv_op_unblock(backing_hd, BLOCK_OP_TYPE_COMMIT_TARGET, + parent->backing_blocker); + bdrv_op_unblock(backing_hd, BLOCK_OP_TYPE_STREAM, + parent->backing_blocker); + /* + * We do backup in 3 ways: + * 1. drive backup + * The target bs is new opened, and the source is top BDS + * 2. blockdev backup + * Both the source and the target are top BDSes. + * 3. internal backup(used for block replication) + * Both the source and the target are backing file + * + * In case 1 and 2, neither the source nor the target is the backing file. + * In case 3, we will block the top BDS, so there is only one block job + * for the top BDS and its backing chain. + */ + bdrv_op_unblock(backing_hd, BLOCK_OP_TYPE_BACKUP_SOURCE, + parent->backing_blocker); + bdrv_op_unblock(backing_hd, BLOCK_OP_TYPE_BACKUP_TARGET, + parent->backing_blocker); +} + +static void bdrv_backing_detach(BdrvChild *c) +{ + BlockDriverState *parent = c->opaque; + + assert(parent->backing_blocker); + bdrv_op_unblock_all(c->bs, parent->backing_blocker); + error_free(parent->backing_blocker); + parent->backing_blocker = NULL; +} + /* * Returns the options and flags that bs->backing should get, based on the * given options and flags for the parent BDS @@ -833,6 +884,8 @@ static void bdrv_backing_options(int *child_flags, QDict *child_options, const BdrvChildRole child_backing = { .get_parent_desc = bdrv_child_get_parent_desc, + .attach = bdrv_backing_attach, + .detach = bdrv_backing_detach, .inherit_options = bdrv_backing_options, .drained_begin = bdrv_child_cb_drained_begin, .drained_end = bdrv_child_cb_drained_end, @@ -1670,6 +1723,9 @@ static void bdrv_replace_child(BdrvChild *child, BlockDriverState *new_bs, if (old_bs->quiesce_counter && child->role->drained_end) { child->role->drained_end(child); } + if (child->role->detach) { + child->role->detach(child); + } QLIST_REMOVE(child, next_parent); /* Update permissions for old node. This is guaranteed to succeed @@ -1693,6 +1749,10 @@ static void bdrv_replace_child(BdrvChild *child, BlockDriverState *new_bs, bdrv_check_perm(new_bs, perm, shared_perm, &error_abort); } bdrv_set_perm(new_bs, perm, shared_perm); + + if (child->role->attach) { + child->role->attach(child); + } } } @@ -1830,52 +1890,17 @@ void bdrv_set_backing_hd(BlockDriverState *bs, BlockDriverState *backing_hd) } if (bs->backing) { - assert(bs->backing_blocker); - bdrv_op_unblock_all(bs->backing->bs, bs->backing_blocker); bdrv_unref_child(bs, bs->backing); - } else if (backing_hd) { - error_setg(&bs->backing_blocker, - "node is used as backing hd of '%s'", - bdrv_get_device_or_node_name(bs)); } if (!backing_hd) { - error_free(bs->backing_blocker); - bs->backing_blocker = NULL; bs->backing = NULL; goto out; } /* FIXME Error handling */ bs->backing = bdrv_attach_child(bs, backing_hd, "backing", &child_backing, &error_abort); - bs->open_flags &= ~BDRV_O_NO_BACKING; - pstrcpy(bs->backing_file, sizeof(bs->backing_file), backing_hd->filename); - pstrcpy(bs->backing_format, sizeof(bs->backing_format), - backing_hd->drv ? backing_hd->drv->format_name : ""); - bdrv_op_block_all(backing_hd, bs->backing_blocker); - /* Otherwise we won't be able to commit or stream */ - bdrv_op_unblock(backing_hd, BLOCK_OP_TYPE_COMMIT_TARGET, - bs->backing_blocker); - bdrv_op_unblock(backing_hd, BLOCK_OP_TYPE_STREAM, - bs->backing_blocker); - /* - * We do backup in 3 ways: - * 1. drive backup - * The target bs is new opened, and the source is top BDS - * 2. blockdev backup - * Both the source and the target are top BDSes. - * 3. internal backup(used for block replication) - * Both the source and the target are backing file - * - * In case 1 and 2, neither the source nor the target is the backing file. - * In case 3, we will block the top BDS, so there is only one block job - * for the top BDS and its backing chain. - */ - bdrv_op_unblock(backing_hd, BLOCK_OP_TYPE_BACKUP_SOURCE, - bs->backing_blocker); - bdrv_op_unblock(backing_hd, BLOCK_OP_TYPE_BACKUP_TARGET, - bs->backing_blocker); out: bdrv_refresh_limits(bs, NULL); } |